Structural buildings are fabricated out of a variety of different materials, and the materials used for the construction of any particular building oftentimes depend upon material availability. For residential units, for example, wood is oftentimes used in North America whereas brick and masonry are used in Europe. Likewise, steel is a common material used in North America and parts of Northern Europe for high-rise or industrial buildings whereas the same structures are fabricated of concrete in South America and some European countries. In North America, because of the limited availability of structural timber and the concerns that have been raised from an environmental standpoint, efforts have been made to identify other types of replacement materials. Acceptable alternative materials must be able to compete favorably, both from a cost standpoint as well as a structural integrity standpoint, within the building industry.
In some proposed systems, it has been found that the connection and continuity at right angle cornered junctions is not only difficult and expensive, but often structurally inadequate under different types of loading conditions, particularly seismic loading. This has been a particular concern in the case of concrete sandwiched panels that have been used to create a unit module designed to provide both the necessary structural strength and the necessary insulative properties. Similarly, a number of tilt-up building systems have been found to perform quite poorly under seismic conditions where the connectors have failed.
Thus, the concerns associated with finding alternatives to known proposals for building systems involve safety, energy efficiency, and environmental impact. In addition, with the rising cost of land and building materials, the cost associated with finding an effective and adequate solution is of significant concern.
It has been found that by using assembly line operations, quality and cost economics can be significantly optimized. In addition, the use of assembly line operations allows adequate training in the use of semi-skilled labor. Thus, in considering alternative building materials and components, it would be desirable to utilize to the extent possible assembly line operations.
A further concern associated with finding an adequate alternative to known building materials and components involves transportation costs and limitations. The ability to transport can oftentimes be a determining factor in the size and weight of prefabricated modules used in the construction of building structures. Similarly, the location of the factory relative to the building site and the intervening transportation logistics can also serve as a restriction. Some potentially promising modular concepts have been limited in application because of the foregoing limitations where large dimensions and excessive weight of the factory modules control the extent and scope of implementation.
In light of the foregoing, a need exists for an alternative to current building units that is structural adequate, environmentally acceptable, energy efficient, and cost effective.
It would also be desirable to provide an alternative to current building units that can be manufactured to meet quality requirements.
A need also exists for an alternative to current building units that is not as susceptible to size and weight restrictions from the standpoint of transportation so that the building units can be manufactured at a factory and subsequently transported to the construction site.